This research program plans to investigate the use of substituted deuterium nuclei as probes of structure in biologically interesting molecules by means of the interpretation of magnetic resonance spectra. A valid method of approximate analysis of the nuclear quadrupole splittings of H2 spectra of asymmetric molecules will be developed in order to obtain the elements of the S tensor describing the molecular orientation. The Hahn double-resonance technique will be used to accumulate additional values of the nuclear quadrupole coupling constants which are needed in the above analysis and also in the analysis of H2 relaxation times. In combination these two kinds of data can give details about the molecular correlation times and the "microdynamical" behavior of molecular groups in lipid membranes, hormones, proteins and other systems of interest. Attempts will be made to provide more intense H2 NMR spectra by using large sample tubes and special probes and sample coils. Chemical shifts in H2 NMR will be exploited to obtain new information on membranes and proteins, taking advantage of their increased resolution and ease of analysis and interpretation.